Electric and hybrid electric vehicles sometimes require the use of a plurality of battery compartments in order to meet the total voltage and/or capacity requirements or to supply auxiliary systems requiring a separate battery compartment. For example, two battery strings or battery packs may be connected in a series configuration in order to double the voltage or in a parallel configuration in order to double the current capacity. In addition a vehicle sub-system may require a completely different voltage than that of the main vehicle battery voltage thus requiring a lower or higher voltage battery pack or string.
Recharging batteries configured in the stated, segmented configuration with a bulk-charging device is not optimal, resulting in uneven battery charging and premature battery failure.